Bu et al. (67) studied the role of PD-1 pathway in regulating and promoting the formation of atherosclerotic lesions, and they found that after the use of blocking anti-PD-1 antibody, hypercholesterolemia Ldlr−/− mice had increased traumatic inflammation and a larger lesion than low-density lipoprotein receptor knockout mice (Ldlr−/−). This evidence concerns the gene PDCD1 and familial hypercholesterolemia.